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 */

using System;
using System.IO;
using System.Collections.Generic;

namespace DotnetPark.NLucene.Analysis.Standard
{
	/// <summary>
	/// Represents a standard analyzer.
	/// </summary>
	public class StandardAnalyzer : Analyzer 
	{
		private Dictionary<string, string> stopTable;

		/// <summary>
		/// An array containing some common English words that are usually not
		/// useful for searching.
		/// </summary>
		public static String[] STOP_WORDS = 
		{
			"a", "and", "are", "as", "at", "be", "but", "by",
			"for", "if", "in", "into", "is", "it",
			"no", "not", "of", "on", "or", "s", "such",
			"t", "that", "the", "their", "then", "there", "these",
			"they", "this", "to", "was", "will", "with"
		};

		/// <summary> Builds an analyzer. </summary>
		public StandardAnalyzer() 
			: this(STOP_WORDS) 
		{
			// use this
		}

		///<summary> Builds an analyzer with the given stop words. </summary>
		public StandardAnalyzer(String[] stopWords) 
		{
			stopTable = StopFilter.MakeStopTable(stopWords);
		}

		/// <summary>
		/// Constructs a StandardTokenizer filtered by a 
		/// StandardFilter, a LowerCaseFilter and a StopFilter.
		/// </summary>
		public override TokenStream TokenStream(String fieldName, TextReader reader) 
		{
			TokenStream result = new StandardTokenizer(reader);
			result = new StandardFilter(result);
			result = new LowerCaseFilter(result);
			result = new StopFilter(result, stopTable);
			return result;
		}
	}
}
